xref: /openbmc/linux/drivers/misc/ocxl/config.c (revision c8ec3743)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2017 IBM Corp.
3 #include <linux/pci.h>
4 #include <asm/pnv-ocxl.h>
5 #include <misc/ocxl.h>
6 #include <misc/ocxl-config.h>
7 
8 #define EXTRACT_BIT(val, bit) (!!(val & BIT(bit)))
9 #define EXTRACT_BITS(val, s, e) ((val & GENMASK(e, s)) >> s)
10 
11 #define OCXL_DVSEC_AFU_IDX_MASK              GENMASK(5, 0)
12 #define OCXL_DVSEC_ACTAG_MASK                GENMASK(11, 0)
13 #define OCXL_DVSEC_PASID_MASK                GENMASK(19, 0)
14 #define OCXL_DVSEC_PASID_LOG_MASK            GENMASK(4, 0)
15 
16 #define OCXL_DVSEC_TEMPL_VERSION         0x0
17 #define OCXL_DVSEC_TEMPL_NAME            0x4
18 #define OCXL_DVSEC_TEMPL_AFU_VERSION     0x1C
19 #define OCXL_DVSEC_TEMPL_MMIO_GLOBAL     0x20
20 #define OCXL_DVSEC_TEMPL_MMIO_GLOBAL_SZ  0x28
21 #define OCXL_DVSEC_TEMPL_MMIO_PP         0x30
22 #define OCXL_DVSEC_TEMPL_MMIO_PP_SZ      0x38
23 #define OCXL_DVSEC_TEMPL_MEM_SZ          0x3C
24 #define OCXL_DVSEC_TEMPL_WWID            0x40
25 
26 #define OCXL_MAX_AFU_PER_FUNCTION 64
27 #define OCXL_TEMPL_LEN            0x58
28 #define OCXL_TEMPL_NAME_LEN       24
29 #define OCXL_CFG_TIMEOUT     3
30 
31 static int find_dvsec(struct pci_dev *dev, int dvsec_id)
32 {
33 	int vsec = 0;
34 	u16 vendor, id;
35 
36 	while ((vsec = pci_find_next_ext_capability(dev, vsec,
37 						    OCXL_EXT_CAP_ID_DVSEC))) {
38 		pci_read_config_word(dev, vsec + OCXL_DVSEC_VENDOR_OFFSET,
39 				&vendor);
40 		pci_read_config_word(dev, vsec + OCXL_DVSEC_ID_OFFSET, &id);
41 		if (vendor == PCI_VENDOR_ID_IBM && id == dvsec_id)
42 			return vsec;
43 	}
44 	return 0;
45 }
46 
47 static int find_dvsec_afu_ctrl(struct pci_dev *dev, u8 afu_idx)
48 {
49 	int vsec = 0;
50 	u16 vendor, id;
51 	u8 idx;
52 
53 	while ((vsec = pci_find_next_ext_capability(dev, vsec,
54 						    OCXL_EXT_CAP_ID_DVSEC))) {
55 		pci_read_config_word(dev, vsec + OCXL_DVSEC_VENDOR_OFFSET,
56 				&vendor);
57 		pci_read_config_word(dev, vsec + OCXL_DVSEC_ID_OFFSET, &id);
58 
59 		if (vendor == PCI_VENDOR_ID_IBM &&
60 			id == OCXL_DVSEC_AFU_CTRL_ID) {
61 			pci_read_config_byte(dev,
62 					vsec + OCXL_DVSEC_AFU_CTRL_AFU_IDX,
63 					&idx);
64 			if (idx == afu_idx)
65 				return vsec;
66 		}
67 	}
68 	return 0;
69 }
70 
71 static int read_pasid(struct pci_dev *dev, struct ocxl_fn_config *fn)
72 {
73 	u16 val;
74 	int pos;
75 
76 	pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_PASID);
77 	if (!pos) {
78 		/*
79 		 * PASID capability is not mandatory, but there
80 		 * shouldn't be any AFU
81 		 */
82 		dev_dbg(&dev->dev, "Function doesn't require any PASID\n");
83 		fn->max_pasid_log = -1;
84 		goto out;
85 	}
86 	pci_read_config_word(dev, pos + PCI_PASID_CAP, &val);
87 	fn->max_pasid_log = EXTRACT_BITS(val, 8, 12);
88 
89 out:
90 	dev_dbg(&dev->dev, "PASID capability:\n");
91 	dev_dbg(&dev->dev, "  Max PASID log = %d\n", fn->max_pasid_log);
92 	return 0;
93 }
94 
95 static int read_dvsec_tl(struct pci_dev *dev, struct ocxl_fn_config *fn)
96 {
97 	int pos;
98 
99 	pos = find_dvsec(dev, OCXL_DVSEC_TL_ID);
100 	if (!pos && PCI_FUNC(dev->devfn) == 0) {
101 		dev_err(&dev->dev, "Can't find TL DVSEC\n");
102 		return -ENODEV;
103 	}
104 	if (pos && PCI_FUNC(dev->devfn) != 0) {
105 		dev_err(&dev->dev, "TL DVSEC is only allowed on function 0\n");
106 		return -ENODEV;
107 	}
108 	fn->dvsec_tl_pos = pos;
109 	return 0;
110 }
111 
112 static int read_dvsec_function(struct pci_dev *dev, struct ocxl_fn_config *fn)
113 {
114 	int pos, afu_present;
115 	u32 val;
116 
117 	pos = find_dvsec(dev, OCXL_DVSEC_FUNC_ID);
118 	if (!pos) {
119 		dev_err(&dev->dev, "Can't find function DVSEC\n");
120 		return -ENODEV;
121 	}
122 	fn->dvsec_function_pos = pos;
123 
124 	pci_read_config_dword(dev, pos + OCXL_DVSEC_FUNC_OFF_INDEX, &val);
125 	afu_present = EXTRACT_BIT(val, 31);
126 	if (!afu_present) {
127 		fn->max_afu_index = -1;
128 		dev_dbg(&dev->dev, "Function doesn't define any AFU\n");
129 		goto out;
130 	}
131 	fn->max_afu_index = EXTRACT_BITS(val, 24, 29);
132 
133 out:
134 	dev_dbg(&dev->dev, "Function DVSEC:\n");
135 	dev_dbg(&dev->dev, "  Max AFU index = %d\n", fn->max_afu_index);
136 	return 0;
137 }
138 
139 static int read_dvsec_afu_info(struct pci_dev *dev, struct ocxl_fn_config *fn)
140 {
141 	int pos;
142 
143 	if (fn->max_afu_index < 0) {
144 		fn->dvsec_afu_info_pos = -1;
145 		return 0;
146 	}
147 
148 	pos = find_dvsec(dev, OCXL_DVSEC_AFU_INFO_ID);
149 	if (!pos) {
150 		dev_err(&dev->dev, "Can't find AFU information DVSEC\n");
151 		return -ENODEV;
152 	}
153 	fn->dvsec_afu_info_pos = pos;
154 	return 0;
155 }
156 
157 static int read_dvsec_vendor(struct pci_dev *dev)
158 {
159 	int pos;
160 	u32 cfg, tlx, dlx;
161 
162 	/*
163 	 * vendor specific DVSEC is optional
164 	 *
165 	 * It's currently only used on function 0 to specify the
166 	 * version of some logic blocks. Some older images may not
167 	 * even have it so we ignore any errors
168 	 */
169 	if (PCI_FUNC(dev->devfn) != 0)
170 		return 0;
171 
172 	pos = find_dvsec(dev, OCXL_DVSEC_VENDOR_ID);
173 	if (!pos)
174 		return 0;
175 
176 	pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_CFG_VERS, &cfg);
177 	pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_TLX_VERS, &tlx);
178 	pci_read_config_dword(dev, pos + OCXL_DVSEC_VENDOR_DLX_VERS, &dlx);
179 
180 	dev_dbg(&dev->dev, "Vendor specific DVSEC:\n");
181 	dev_dbg(&dev->dev, "  CFG version = 0x%x\n", cfg);
182 	dev_dbg(&dev->dev, "  TLX version = 0x%x\n", tlx);
183 	dev_dbg(&dev->dev, "  DLX version = 0x%x\n", dlx);
184 	return 0;
185 }
186 
187 static int validate_function(struct pci_dev *dev, struct ocxl_fn_config *fn)
188 {
189 	if (fn->max_pasid_log == -1 && fn->max_afu_index >= 0) {
190 		dev_err(&dev->dev,
191 			"AFUs are defined but no PASIDs are requested\n");
192 		return -EINVAL;
193 	}
194 
195 	if (fn->max_afu_index > OCXL_MAX_AFU_PER_FUNCTION) {
196 		dev_err(&dev->dev,
197 			"Max AFU index out of architectural limit (%d vs %d)\n",
198 			fn->max_afu_index, OCXL_MAX_AFU_PER_FUNCTION);
199 		return -EINVAL;
200 	}
201 	return 0;
202 }
203 
204 int ocxl_config_read_function(struct pci_dev *dev, struct ocxl_fn_config *fn)
205 {
206 	int rc;
207 
208 	rc = read_pasid(dev, fn);
209 	if (rc) {
210 		dev_err(&dev->dev, "Invalid PASID configuration: %d\n", rc);
211 		return -ENODEV;
212 	}
213 
214 	rc = read_dvsec_tl(dev, fn);
215 	if (rc) {
216 		dev_err(&dev->dev,
217 			"Invalid Transaction Layer DVSEC configuration: %d\n",
218 			rc);
219 		return -ENODEV;
220 	}
221 
222 	rc = read_dvsec_function(dev, fn);
223 	if (rc) {
224 		dev_err(&dev->dev,
225 			"Invalid Function DVSEC configuration: %d\n", rc);
226 		return -ENODEV;
227 	}
228 
229 	rc = read_dvsec_afu_info(dev, fn);
230 	if (rc) {
231 		dev_err(&dev->dev, "Invalid AFU configuration: %d\n", rc);
232 		return -ENODEV;
233 	}
234 
235 	rc = read_dvsec_vendor(dev);
236 	if (rc) {
237 		dev_err(&dev->dev,
238 			"Invalid vendor specific DVSEC configuration: %d\n",
239 			rc);
240 		return -ENODEV;
241 	}
242 
243 	rc = validate_function(dev, fn);
244 	return rc;
245 }
246 EXPORT_SYMBOL_GPL(ocxl_config_read_function);
247 
248 static int read_afu_info(struct pci_dev *dev, struct ocxl_fn_config *fn,
249 			int offset, u32 *data)
250 {
251 	u32 val;
252 	unsigned long timeout = jiffies + (HZ * OCXL_CFG_TIMEOUT);
253 	int pos = fn->dvsec_afu_info_pos;
254 
255 	/* Protect 'data valid' bit */
256 	if (EXTRACT_BIT(offset, 31)) {
257 		dev_err(&dev->dev, "Invalid offset in AFU info DVSEC\n");
258 		return -EINVAL;
259 	}
260 
261 	pci_write_config_dword(dev, pos + OCXL_DVSEC_AFU_INFO_OFF, offset);
262 	pci_read_config_dword(dev, pos + OCXL_DVSEC_AFU_INFO_OFF, &val);
263 	while (!EXTRACT_BIT(val, 31)) {
264 		if (time_after_eq(jiffies, timeout)) {
265 			dev_err(&dev->dev,
266 				"Timeout while reading AFU info DVSEC (offset=%d)\n",
267 				offset);
268 			return -EBUSY;
269 		}
270 		cpu_relax();
271 		pci_read_config_dword(dev, pos + OCXL_DVSEC_AFU_INFO_OFF, &val);
272 	}
273 	pci_read_config_dword(dev, pos + OCXL_DVSEC_AFU_INFO_DATA, data);
274 	return 0;
275 }
276 
277 int ocxl_config_check_afu_index(struct pci_dev *dev,
278 				struct ocxl_fn_config *fn, int afu_idx)
279 {
280 	u32 val;
281 	int rc, templ_major, templ_minor, len;
282 
283 	pci_write_config_byte(dev,
284 			fn->dvsec_afu_info_pos + OCXL_DVSEC_AFU_INFO_AFU_IDX,
285 			afu_idx);
286 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_VERSION, &val);
287 	if (rc)
288 		return rc;
289 
290 	/* AFU index map can have holes */
291 	if (!val)
292 		return 0;
293 
294 	templ_major = EXTRACT_BITS(val, 8, 15);
295 	templ_minor = EXTRACT_BITS(val, 0, 7);
296 	dev_dbg(&dev->dev, "AFU descriptor template version %d.%d\n",
297 		templ_major, templ_minor);
298 
299 	len = EXTRACT_BITS(val, 16, 31);
300 	if (len != OCXL_TEMPL_LEN) {
301 		dev_warn(&dev->dev,
302 			"Unexpected template length in AFU information (%#x)\n",
303 			len);
304 	}
305 	return 1;
306 }
307 EXPORT_SYMBOL_GPL(ocxl_config_check_afu_index);
308 
309 static int read_afu_name(struct pci_dev *dev, struct ocxl_fn_config *fn,
310 			struct ocxl_afu_config *afu)
311 {
312 	int i, rc;
313 	u32 val, *ptr;
314 
315 	BUILD_BUG_ON(OCXL_AFU_NAME_SZ < OCXL_TEMPL_NAME_LEN);
316 	for (i = 0; i < OCXL_TEMPL_NAME_LEN; i += 4) {
317 		rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_NAME + i, &val);
318 		if (rc)
319 			return rc;
320 		ptr = (u32 *) &afu->name[i];
321 		*ptr = le32_to_cpu((__force __le32) val);
322 	}
323 	afu->name[OCXL_AFU_NAME_SZ - 1] = '\0'; /* play safe */
324 	return 0;
325 }
326 
327 static int read_afu_mmio(struct pci_dev *dev, struct ocxl_fn_config *fn,
328 			struct ocxl_afu_config *afu)
329 {
330 	int rc;
331 	u32 val;
332 
333 	/*
334 	 * Global MMIO
335 	 */
336 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_GLOBAL, &val);
337 	if (rc)
338 		return rc;
339 	afu->global_mmio_bar = EXTRACT_BITS(val, 0, 2);
340 	afu->global_mmio_offset = EXTRACT_BITS(val, 16, 31) << 16;
341 
342 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_GLOBAL + 4, &val);
343 	if (rc)
344 		return rc;
345 	afu->global_mmio_offset += (u64) val << 32;
346 
347 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_GLOBAL_SZ, &val);
348 	if (rc)
349 		return rc;
350 	afu->global_mmio_size = val;
351 
352 	/*
353 	 * Per-process MMIO
354 	 */
355 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_PP, &val);
356 	if (rc)
357 		return rc;
358 	afu->pp_mmio_bar = EXTRACT_BITS(val, 0, 2);
359 	afu->pp_mmio_offset = EXTRACT_BITS(val, 16, 31) << 16;
360 
361 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_PP + 4, &val);
362 	if (rc)
363 		return rc;
364 	afu->pp_mmio_offset += (u64) val << 32;
365 
366 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MMIO_PP_SZ, &val);
367 	if (rc)
368 		return rc;
369 	afu->pp_mmio_stride = val;
370 
371 	return 0;
372 }
373 
374 static int read_afu_control(struct pci_dev *dev, struct ocxl_afu_config *afu)
375 {
376 	int pos;
377 	u8 val8;
378 	u16 val16;
379 
380 	pos = find_dvsec_afu_ctrl(dev, afu->idx);
381 	if (!pos) {
382 		dev_err(&dev->dev, "Can't find AFU control DVSEC for AFU %d\n",
383 			afu->idx);
384 		return -ENODEV;
385 	}
386 	afu->dvsec_afu_control_pos = pos;
387 
388 	pci_read_config_byte(dev, pos + OCXL_DVSEC_AFU_CTRL_PASID_SUP, &val8);
389 	afu->pasid_supported_log = EXTRACT_BITS(val8, 0, 4);
390 
391 	pci_read_config_word(dev, pos + OCXL_DVSEC_AFU_CTRL_ACTAG_SUP, &val16);
392 	afu->actag_supported = EXTRACT_BITS(val16, 0, 11);
393 	return 0;
394 }
395 
396 static bool char_allowed(int c)
397 {
398 	/*
399 	 * Permitted Characters : Alphanumeric, hyphen, underscore, comma
400 	 */
401 	if ((c >= 0x30 && c <= 0x39) /* digits */ ||
402 		(c >= 0x41 && c <= 0x5A) /* upper case */ ||
403 		(c >= 0x61 && c <= 0x7A) /* lower case */ ||
404 		c == 0 /* NULL */ ||
405 		c == 0x2D /* - */ ||
406 		c == 0x5F /* _ */ ||
407 		c == 0x2C /* , */)
408 		return true;
409 	return false;
410 }
411 
412 static int validate_afu(struct pci_dev *dev, struct ocxl_afu_config *afu)
413 {
414 	int i;
415 
416 	if (!afu->name[0]) {
417 		dev_err(&dev->dev, "Empty AFU name\n");
418 		return -EINVAL;
419 	}
420 	for (i = 0; i < OCXL_TEMPL_NAME_LEN; i++) {
421 		if (!char_allowed(afu->name[i])) {
422 			dev_err(&dev->dev,
423 				"Invalid character in AFU name\n");
424 			return -EINVAL;
425 		}
426 	}
427 
428 	if (afu->global_mmio_bar != 0 &&
429 		afu->global_mmio_bar != 2 &&
430 		afu->global_mmio_bar != 4) {
431 		dev_err(&dev->dev, "Invalid global MMIO bar number\n");
432 		return -EINVAL;
433 	}
434 	if (afu->pp_mmio_bar != 0 &&
435 		afu->pp_mmio_bar != 2 &&
436 		afu->pp_mmio_bar != 4) {
437 		dev_err(&dev->dev, "Invalid per-process MMIO bar number\n");
438 		return -EINVAL;
439 	}
440 	return 0;
441 }
442 
443 int ocxl_config_read_afu(struct pci_dev *dev, struct ocxl_fn_config *fn,
444 			struct ocxl_afu_config *afu, u8 afu_idx)
445 {
446 	int rc;
447 	u32 val32;
448 
449 	/*
450 	 * First, we need to write the AFU idx for the AFU we want to
451 	 * access.
452 	 */
453 	WARN_ON((afu_idx & OCXL_DVSEC_AFU_IDX_MASK) != afu_idx);
454 	afu->idx = afu_idx;
455 	pci_write_config_byte(dev,
456 			fn->dvsec_afu_info_pos + OCXL_DVSEC_AFU_INFO_AFU_IDX,
457 			afu->idx);
458 
459 	rc = read_afu_name(dev, fn, afu);
460 	if (rc)
461 		return rc;
462 
463 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_AFU_VERSION, &val32);
464 	if (rc)
465 		return rc;
466 	afu->version_major = EXTRACT_BITS(val32, 24, 31);
467 	afu->version_minor = EXTRACT_BITS(val32, 16, 23);
468 	afu->afuc_type = EXTRACT_BITS(val32, 14, 15);
469 	afu->afum_type = EXTRACT_BITS(val32, 12, 13);
470 	afu->profile = EXTRACT_BITS(val32, 0, 7);
471 
472 	rc = read_afu_mmio(dev, fn, afu);
473 	if (rc)
474 		return rc;
475 
476 	rc = read_afu_info(dev, fn, OCXL_DVSEC_TEMPL_MEM_SZ, &val32);
477 	if (rc)
478 		return rc;
479 	afu->log_mem_size = EXTRACT_BITS(val32, 0, 7);
480 
481 	rc = read_afu_control(dev, afu);
482 	if (rc)
483 		return rc;
484 
485 	dev_dbg(&dev->dev, "AFU configuration:\n");
486 	dev_dbg(&dev->dev, "  name = %s\n", afu->name);
487 	dev_dbg(&dev->dev, "  version = %d.%d\n", afu->version_major,
488 		afu->version_minor);
489 	dev_dbg(&dev->dev, "  global mmio bar = %hhu\n", afu->global_mmio_bar);
490 	dev_dbg(&dev->dev, "  global mmio offset = %#llx\n",
491 		afu->global_mmio_offset);
492 	dev_dbg(&dev->dev, "  global mmio size = %#x\n", afu->global_mmio_size);
493 	dev_dbg(&dev->dev, "  pp mmio bar = %hhu\n", afu->pp_mmio_bar);
494 	dev_dbg(&dev->dev, "  pp mmio offset = %#llx\n", afu->pp_mmio_offset);
495 	dev_dbg(&dev->dev, "  pp mmio stride = %#x\n", afu->pp_mmio_stride);
496 	dev_dbg(&dev->dev, "  mem size (log) = %hhu\n", afu->log_mem_size);
497 	dev_dbg(&dev->dev, "  pasid supported (log) = %u\n",
498 		afu->pasid_supported_log);
499 	dev_dbg(&dev->dev, "  actag supported = %u\n",
500 		afu->actag_supported);
501 
502 	rc = validate_afu(dev, afu);
503 	return rc;
504 }
505 EXPORT_SYMBOL_GPL(ocxl_config_read_afu);
506 
507 int ocxl_config_get_actag_info(struct pci_dev *dev, u16 *base, u16 *enabled,
508 			u16 *supported)
509 {
510 	int rc;
511 
512 	/*
513 	 * This is really a simple wrapper for the kernel API, to
514 	 * avoid an external driver using ocxl as a library to call
515 	 * platform-dependent code
516 	 */
517 	rc = pnv_ocxl_get_actag(dev, base, enabled, supported);
518 	if (rc) {
519 		dev_err(&dev->dev, "Can't get actag for device: %d\n", rc);
520 		return rc;
521 	}
522 	return 0;
523 }
524 EXPORT_SYMBOL_GPL(ocxl_config_get_actag_info);
525 
526 void ocxl_config_set_afu_actag(struct pci_dev *dev, int pos, int actag_base,
527 			int actag_count)
528 {
529 	u16 val;
530 
531 	val = actag_count & OCXL_DVSEC_ACTAG_MASK;
532 	pci_write_config_byte(dev, pos + OCXL_DVSEC_AFU_CTRL_ACTAG_EN, val);
533 
534 	val = actag_base & OCXL_DVSEC_ACTAG_MASK;
535 	pci_write_config_dword(dev, pos + OCXL_DVSEC_AFU_CTRL_ACTAG_BASE, val);
536 }
537 EXPORT_SYMBOL_GPL(ocxl_config_set_afu_actag);
538 
539 int ocxl_config_get_pasid_info(struct pci_dev *dev, int *count)
540 {
541 	return pnv_ocxl_get_pasid_count(dev, count);
542 }
543 EXPORT_SYMBOL_GPL(ocxl_config_get_pasid_info);
544 
545 void ocxl_config_set_afu_pasid(struct pci_dev *dev, int pos, int pasid_base,
546 			u32 pasid_count_log)
547 {
548 	u8 val8;
549 	u32 val32;
550 
551 	val8 = pasid_count_log & OCXL_DVSEC_PASID_LOG_MASK;
552 	pci_write_config_byte(dev, pos + OCXL_DVSEC_AFU_CTRL_PASID_EN, val8);
553 
554 	pci_read_config_dword(dev, pos + OCXL_DVSEC_AFU_CTRL_PASID_BASE,
555 			&val32);
556 	val32 &= ~OCXL_DVSEC_PASID_MASK;
557 	val32 |= pasid_base & OCXL_DVSEC_PASID_MASK;
558 	pci_write_config_dword(dev, pos + OCXL_DVSEC_AFU_CTRL_PASID_BASE,
559 			val32);
560 }
561 EXPORT_SYMBOL_GPL(ocxl_config_set_afu_pasid);
562 
563 void ocxl_config_set_afu_state(struct pci_dev *dev, int pos, int enable)
564 {
565 	u8 val;
566 
567 	pci_read_config_byte(dev, pos + OCXL_DVSEC_AFU_CTRL_ENABLE, &val);
568 	if (enable)
569 		val |= 1;
570 	else
571 		val &= 0xFE;
572 	pci_write_config_byte(dev, pos + OCXL_DVSEC_AFU_CTRL_ENABLE, val);
573 }
574 EXPORT_SYMBOL_GPL(ocxl_config_set_afu_state);
575 
576 int ocxl_config_set_TL(struct pci_dev *dev, int tl_dvsec)
577 {
578 	u32 val;
579 	__be32 *be32ptr;
580 	u8 timers;
581 	int i, rc;
582 	long recv_cap;
583 	char *recv_rate;
584 
585 	/*
586 	 * Skip on function != 0, as the TL can only be defined on 0
587 	 */
588 	if (PCI_FUNC(dev->devfn) != 0)
589 		return 0;
590 
591 	recv_rate = kzalloc(PNV_OCXL_TL_RATE_BUF_SIZE, GFP_KERNEL);
592 	if (!recv_rate)
593 		return -ENOMEM;
594 	/*
595 	 * The spec defines 64 templates for messages in the
596 	 * Transaction Layer (TL).
597 	 *
598 	 * The host and device each support a subset, so we need to
599 	 * configure the transmitters on each side to send only
600 	 * templates the receiver understands, at a rate the receiver
601 	 * can process.  Per the spec, template 0 must be supported by
602 	 * everybody. That's the template which has been used by the
603 	 * host and device so far.
604 	 *
605 	 * The sending rate limit must be set before the template is
606 	 * enabled.
607 	 */
608 
609 	/*
610 	 * Device -> host
611 	 */
612 	rc = pnv_ocxl_get_tl_cap(dev, &recv_cap, recv_rate,
613 				PNV_OCXL_TL_RATE_BUF_SIZE);
614 	if (rc)
615 		goto out;
616 
617 	for (i = 0; i < PNV_OCXL_TL_RATE_BUF_SIZE; i += 4) {
618 		be32ptr = (__be32 *) &recv_rate[i];
619 		pci_write_config_dword(dev,
620 				tl_dvsec + OCXL_DVSEC_TL_SEND_RATE + i,
621 				be32_to_cpu(*be32ptr));
622 	}
623 	val = recv_cap >> 32;
624 	pci_write_config_dword(dev, tl_dvsec + OCXL_DVSEC_TL_SEND_CAP, val);
625 	val = recv_cap & GENMASK(31, 0);
626 	pci_write_config_dword(dev, tl_dvsec + OCXL_DVSEC_TL_SEND_CAP + 4, val);
627 
628 	/*
629 	 * Host -> device
630 	 */
631 	for (i = 0; i < PNV_OCXL_TL_RATE_BUF_SIZE; i += 4) {
632 		pci_read_config_dword(dev,
633 				tl_dvsec + OCXL_DVSEC_TL_RECV_RATE + i,
634 				&val);
635 		be32ptr = (__be32 *) &recv_rate[i];
636 		*be32ptr = cpu_to_be32(val);
637 	}
638 	pci_read_config_dword(dev, tl_dvsec + OCXL_DVSEC_TL_RECV_CAP, &val);
639 	recv_cap = (long) val << 32;
640 	pci_read_config_dword(dev, tl_dvsec + OCXL_DVSEC_TL_RECV_CAP + 4, &val);
641 	recv_cap |= val;
642 
643 	rc = pnv_ocxl_set_tl_conf(dev, recv_cap, __pa(recv_rate),
644 				PNV_OCXL_TL_RATE_BUF_SIZE);
645 	if (rc)
646 		goto out;
647 
648 	/*
649 	 * Opencapi commands needing to be retried are classified per
650 	 * the TL in 2 groups: short and long commands.
651 	 *
652 	 * The short back off timer it not used for now. It will be
653 	 * for opencapi 4.0.
654 	 *
655 	 * The long back off timer is typically used when an AFU hits
656 	 * a page fault but the NPU is already processing one. So the
657 	 * AFU needs to wait before it can resubmit. Having a value
658 	 * too low doesn't break anything, but can generate extra
659 	 * traffic on the link.
660 	 * We set it to 1.6 us for now. It's shorter than, but in the
661 	 * same order of magnitude as the time spent to process a page
662 	 * fault.
663 	 */
664 	timers = 0x2 << 4; /* long timer = 1.6 us */
665 	pci_write_config_byte(dev, tl_dvsec + OCXL_DVSEC_TL_BACKOFF_TIMERS,
666 			timers);
667 
668 	rc = 0;
669 out:
670 	kfree(recv_rate);
671 	return rc;
672 }
673 EXPORT_SYMBOL_GPL(ocxl_config_set_TL);
674 
675 int ocxl_config_terminate_pasid(struct pci_dev *dev, int afu_control, int pasid)
676 {
677 	u32 val;
678 	unsigned long timeout;
679 
680 	pci_read_config_dword(dev, afu_control + OCXL_DVSEC_AFU_CTRL_TERM_PASID,
681 			&val);
682 	if (EXTRACT_BIT(val, 20)) {
683 		dev_err(&dev->dev,
684 			"Can't terminate PASID %#x, previous termination didn't complete\n",
685 			pasid);
686 		return -EBUSY;
687 	}
688 
689 	val &= ~OCXL_DVSEC_PASID_MASK;
690 	val |= pasid & OCXL_DVSEC_PASID_MASK;
691 	val |= BIT(20);
692 	pci_write_config_dword(dev,
693 			afu_control + OCXL_DVSEC_AFU_CTRL_TERM_PASID,
694 			val);
695 
696 	timeout = jiffies + (HZ * OCXL_CFG_TIMEOUT);
697 	pci_read_config_dword(dev, afu_control + OCXL_DVSEC_AFU_CTRL_TERM_PASID,
698 			&val);
699 	while (EXTRACT_BIT(val, 20)) {
700 		if (time_after_eq(jiffies, timeout)) {
701 			dev_err(&dev->dev,
702 				"Timeout while waiting for AFU to terminate PASID %#x\n",
703 				pasid);
704 			return -EBUSY;
705 		}
706 		cpu_relax();
707 		pci_read_config_dword(dev,
708 				afu_control + OCXL_DVSEC_AFU_CTRL_TERM_PASID,
709 				&val);
710 	}
711 	return 0;
712 }
713 EXPORT_SYMBOL_GPL(ocxl_config_terminate_pasid);
714 
715 void ocxl_config_set_actag(struct pci_dev *dev, int func_dvsec, u32 tag_first,
716 			u32 tag_count)
717 {
718 	u32 val;
719 
720 	val = (tag_first & OCXL_DVSEC_ACTAG_MASK) << 16;
721 	val |= tag_count & OCXL_DVSEC_ACTAG_MASK;
722 	pci_write_config_dword(dev, func_dvsec + OCXL_DVSEC_FUNC_OFF_ACTAG,
723 			val);
724 }
725 EXPORT_SYMBOL_GPL(ocxl_config_set_actag);
726